This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The specific aims are: 1. In vitro cellular assays of sweet protein-receptor interactions. 2. To use NMR spectroscopy to investigate the conformational and dynamic requirements in brazzein for its interaction and activation of the sweet taste receptor. These studies will serve to identify changes that correlate with fuctional properties. 3. To monitor binding of brazzein and its mutants to T1R2/T1R3 sweet receptor and its mutants by STDD-NMR spectroscopy. These results will contribute to accurately define the essential molecular features responsible for the brazzein-sweet receptor interaction and the resulting signal transduction non-caloric sweeteners as an approach to help addressing diabetes and related disorders.